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Biomedical subjects

T S Lee

Publications and source records attributed to T S Lee.

At least 37 records · Page 2Linked to original sources
PubMed2001

Incomplete miscarriage: a randomized controlled trial comparing oral with vaginal misoprostol for medical evacuation.

BACKGROUND: A prospective randomized controlled trial was conducted to compare the efficacy and side-effects of vaginal versus oral misoprostol in the medical management of incomplete miscarriage. METHODS: Two hundred and one patients who miscarried consented to randomization using computer-generated randomization model prior to treatment. A total of 800 microg of misoprostol was given either vaginally or orally to the randomized subjects. A second dose was repeated 4 h later if the product of conception had not been passed. RESULTS: The incidence of complete uterine evacuation following vaginal and oral misoprostol was similar [(58/95) 61.1% versus (67/103) 64.4%]. There was a significantly decreased incidence of diarrhoea [(12/95) 13.6% versus (62/103) 65.3%, P < 0.01] with the use of vaginal misoprostol. CONCLUSIONS: Vaginal misoprostol was as effective as oral misoprostol in medical uterine evacuation in patients with incomplete miscarriage. There was also a reduction in the incidence of diarrhoea with the use of vaginal misoprostol.

Abortion, Incomplete↗
PubMed2001

Comparison of intraoperative frozen section analysis of sentinel node with preoperative positron emission tomography in the diagnosis of axillary lymph node status in breast cancer patients.

BACKGROUND: Although axillary lymph node status is an important prognostic factor and axillary dissection is regarded as the gold standard for staging, it requires radical surgery which is accompanied by considerable postoperative problems such as lymphedema. This study was carried out to evaluate the diagnostic accuracy of preoperative positron emission tomography (PET) and intraoperative frozen biopsy of sentinel lymphadenectomy (SLND) in detecting axillary lymph node metastasis. METHODS: We studied 18 patients who had preoperative PET and SLND for breast cancer in the Department of Surgery at Samsung Medical Center. They all had preoperative PET with a radiolabeled glucose analogue ([18F]FDG) to visualize primary tumors and metastatic nodes. Isosulphan blue dye was used for intraoperative SLND. Frozen and permanent biopsies were then compared after full axillary dissection. RESULTS: In 18 cases, six had positive metastatic nodes in the permanent biopsy of full axillary dissection but were negative in three cases by preoperative PET. There was one false negative result by frozen biopsy of SLND which was later shown to be positive by permanent biopsy. The sensitivity and specificity of SLND and PET for detecting axillary node metastasis were 83, 100% and 50, 100%, respectively. CONCLUSION: Although both methods are good for axillary nodal status, the intraoperative frozen biopsy result of SLND was superior to preoperative PET in our preliminary study.

Adult↗
PubMed2001

Endonasal dacryocystorhinostomy in the primary treatment of acute dacryocystitis with abscess formation.

PURPOSE: To determine whether endonasal dacryocystorhinostomy may constitute effective primary treatment of acute dacryocystitis with lacrimal sac abscess formation. METHODS: This was a retrospective review of a series of 24 patients with acute dacryocystitis and lacrimal sac abscess who underwent endonasal dacryocystorhinostomy as a primary procedure. Outcome measures included resolution of signs and symptoms of acute dacryocystitis as well as intranasal ostium patency as assessed by lacrimal irrigation. RESULTS: Pain was relieved in all patients within 3 days of surgery, and swelling resolved in all patients by 9 days after surgery. Ostium patency, as defined by the absence of epiphora, and free lacrimal irrigation was achieved in 20 (83%) of 24 patients, with follow-up of 27 to 59 months (mean, 40 months). Recurrent epiphora developed in four patients; recurrent dacryocystitis developed in none. CONCLUSIONS: Endonasal dacryocystorhinostomy may be a useful option in the treatment of acute dacryocystitis with abscess formation.

Abscess↗
PubMed2001

Iliopectineal bursitis complicating hemiarthroplasty: a case report.

Enlarged iliopectineal bursitis in the hip region, which usually occurs with degenerative, infectious, or traumatic disorders, is relatively rare. Iliopectineal bursitis complicating bipolar hemiarthroplasty is even more rare. Reported here is an unusual case of a patient with an inguinal mass presenting 8 years after bipolar hemiarthroplasty. Enlarged bursitis complicating the hip prosthesis is rare and has been described only anecdotally in the literature. The enlarged iliopectineal bursa arises from the hip, and the most apparent cause of its formation is polyethylene debris. Treatment should be directed at the source of the debris intraarticularly. Wearing of the polyethylene insert was difficult to discern radiographically for this patient; it was seen on the scout film of the computed tomography of the pelvis while evaluating the enlarged bursitis. The scout film of the computed tomography and the two-dimensional reconstruction of computed tomograms of the hip may be helpful in evaluating wearing of the polyethylene insert.

Arthroplasty, Replacement, Hip↗
PubMed2001

Roles of alpha(1) and alpha(1)/beta subunits derived from cardiac L-type Ca(2+) channels on voltage-dependent facilitation mechanisms.

Strong depolarization pulses facilitate L-type Ca(2+) channels in various cell types including cardiac myocytes. The mechanisms underlying prepulse facilitation are controversial with respect to the requirements for channel subunits, cAMP-dependent protein kinase, and additional anchor proteins. The properties of voltage-dependent facilitation of the L-type Ca(2+) channel was studied in recombinant cardiac alpha(1) subunits with or without cardiac beta subunit, expressed in Chinese hamster fibroblast cells. The magnitude of voltage-dependent I(Ba) facilitation in the alpha(1) subunit channel is dependent on the duration of the prepulse as well as on the interval duration between prepulse and test pulse. The characteristics of this facilitation were not affected by coexpression of the beta subunit. These results indicate that cardiac alpha(1) subunits exhibit voltage-dependent facilitation because of their own intrinsic structure, independent of any other accessory subunit or additional regulatory proteins, and that cardiac beta subunits have no essential regulatory role at the onset or continuance of the voltage-dependent facilitation.

Animals↗
PubMed2001

Chylous ascites in acute pancreatitis during pregnancy: case report.

Chylous ascites is a rare clinical manifestation characterized by ascitic chylomicrons resulting from mechanical obstruction of or leakage from the lymphatic channel. Chronic disorders, especially malignancies, account for most cases of chylous ascites. Acute chylous ascites is less common than the chronic form. We present a rare case of acute chylous ascites secondary to acute pancreatitis during the third trimester of pregnancy. This 24-year-old woman was referred to our emergency department because of severe epigastralgia for several days. Abdominal computed tomography revealed diffuse enlargement of the pancreas and peripancreatic exudation. Massive chylous ascites was found during emergent abdominal exploratory laparotomy. An emergent cesarean section was done because of fetal distress and there was no further accumulation of chyle. A pancreaticocutaneous fistula resulting from the cesarean section was treated successfully with a fistulectomy. In conclusion, chylous ascites is a rare complication of acute pancreatitis. Cesarean section may be helpful in terminating chylous accumulation in acute pancreatitis during the third trimester of pregnancy.

Acute Disease↗
PubMed2001

Tuberculous synovitis of the elbow joint.

Tuberculous synovitis in the elbow joint is extremely rare in developed countries. We describe a 68-year-old man who had had a gradually enlarging mass over the volar side of the left proximal forearm near the elbow joint for 4 months. Plain roentgenograms of the diseased elbow showed early osteoarthritic change. Magnetic resonance imaging revealed diffuse synovitis with a large 8 x 8 cm extra-articular synovial cyst. Synovectomy was performed and histopathologic examination of the surgical specimen revealed granulomatous inflammation with caseation, prominent Langhan's giant cells, and sparse acid-fast bacilli. The patient had been receiving antituberculous chemotherapy for at least 8 months at the time of examination and had no recurrence of swelling or discharging sinuses during follow-up. Differential diagnoses in patients with elbow swelling should include pigmented villonodular synovitis, hemophilic arthropathy, rheumatoid arthritis, degenerative joint disease, and tuberculosis. Simple aspiration may enable earlier diagnosis, before destructive arthropathy becomes advanced.

Aged↗
PubMed2000

Rapid, efficient detection and drug susceptibility testing of Mycobacterium tuberculosis in sputum by microscopic observation of broth cultures. The Tuberculosis Working Group in Peru.

Inexpensive, rapid, and reliable methods of detecting infection by and drug susceptibility of Mycobacterium tuberculosis (MTB) are crucial to the control of tuberculosis. The novel microscopic observation broth-drug susceptibility assay (MODS) detects early growth of MTB in liquid medium, allowing more timely diagnosis and drug susceptibility testing. Sputum samples from hospitalized patients in Peru were analyzed by using stains, culture, and PCR. Sensitivity of MODS (92%) compared favorably with the most sensitive of the other culture methods (93%). Sputum samples positive for tuberculosis were tested for susceptibility to isoniazid and rifampin with the microwell alamar blue assay (MABA) and MODS. In 89% of cases, there was concordance between MODS and MABA. Of the diagnostic and susceptibility testing methods used, MODS yielded results most rapidly (median, 9.0 and 9.5 days, respectively). MODS is a rapid, inexpensive, sensitive, and specific method for MTB detection and susceptibility testing; it is particularly appropriate for use in developing countries burdened by significant infection rates and increasing numbers of multiple-drug-resistant cases.

Antitubercular Agents↗
PubMed2000

The role of nitric oxide and prostaglandin E2 on the hyperalgesia induced by excitatory amino acids in rats.

The present study was designed to investigate the role of nitric oxide (NO), N-methyl-D-aspartate (NMDA) receptor and prostaglandins on hyperalgesia induced in rats by excitatory amino acids and the possibility that prostaglandins may act as the retrograde messenger in the spinal cord like NO. Nomega-nitro-L-arginine methyl ester (L-NAME; 500 microg/paw, intraplantarly (i.pl.)), MK-801 (10 microg/paw, i.pl.) or indomethacin (300 microg/paw, i.pl.) reduced the duration of phase 2 of the biting/licking and scratching (B/L + S) response induced by formalin injection from 255.6+/-16.7 s to 155.6+/-16.9, 172.25+/-33.3 or 205.6+/-16.7 s, respectively. L-NAME (0.3 mg, i.th.), MK-801 (8 microg, i.th.) or indomethacin (20 microg, i.th) reduced the duration of phase 2 of the B/L + S response induced by saline injection from 288.5+/-7.7s to 207.7+/-19.2, 184.6+/-7.7 or 1923+/-38.5 s, respectively. L-NAME or indomethacin injected into the spinal cord of the rat significantly reduced the hyperalgesia induced by NMDA (1 microg, i.th.) from 43.8+/-4.6% to 12.3+/-3.1 and 19.2+/-2.3%, respectively. It is assumed that NO produced by excitatory amino acids may increase prostaglandin production by cyclooxygenase activation. L-NAME, MK-801 or indomethacin injected into the rat spinal cord significantly reduced the hyperalgesia induced by prostaglandin E2 (PGE2, 25 ng, i.th.) in the tail-flick test from 40.6+/-3.5% to 18.2+/-3.2, 18.8+/-1.8 or 17.6+/-4.1%, respectively, but had little effect on hyperalgesia in the paw pressure test (except for indomethacin). In conclusion, NO and PGE2 affect the hyperalgesia induced by excitatory amino acids. It is suggested that PGE2, like NO, may act as a retrograde messenger in the spinal cord.

Animals↗
PubMed2000

Morphologic change of the internal elastic lamina in Buerger's disease.

Morphologic features and pathogenesis of arterial changes occurring in Buerger's disease (thromboangiitis obliterans) are still controversial. This study describes histopathologic features of medium sized arteries from patients with Buerger's disease, particularly of the internal elastic lamina in relation to the immunologic mechanism of the injury. Seventeen segments of occluded arteries (femoral or popliteal arteries) from 17 patients with Buerger's disease were analyzed by histopathological and immunohistochemical methods. The most characteristic features were total luminal obliteration, together with a varying degree of recanalization and deposition of hemosiderin pigments. Detailed analysis, however, showed marked undulation and multiplication of the internal elastic lamina (100%) associated with basophilic degeneration and delicate linear calcification (47%). Lymphocytic infiltration along the internal elastic lamina was seen in 71% and was associated with localized edema. Lymphocytes along the lamina were consistently positive for T cell marker. Mild to moderate fibrosis was present at the media in 24%. Adventitial changes included mild, nonspecific and irregular fibrosis seen in 53%. Immunologic injury to the internal elastic lamina associated with T-lymphocytic infiltration might be the initial morphogenetic mechanism of the thrombotic occlusion and organization of medium-sized arteries in Buerger's disease.

Adult↗
PubMed2000

p53 codon 72 polymorphism and risk of cervical carcinoma in Korean women.

A common polymorphism of the wild type p53 is known at codon 72 of exon 4, with 2 alleles encoding either arginine (CGC, p53Arg) or proline (CCC, p53Pro). A recent study suggested that this polymorphism affects the susceptibility of p53 protein to human papillomavirus E6 oncoprotein mediated degradation and that individuals homozygous for p53Arg are seven times more susceptible to HPV-associated carcinogenesis of the cervix than heterozygotes. To examine whether the p53Arg genotype could be a risk factor for HPV-associated cervical carcinomas in the Korean population, we analyzed the p53 codon 72 polymorphism status of HPV-positive invasive cervical carcinomas from 52 Korean women and 103 healthy control samples. The proportion of individuals homozygous for p53Arg, homozygous for p53Pro, and heterozygous for the two alleles were 40%, 19%, and 41% in normal healthy controls; 42%, 17%, and 40% in women with HPV-positive invasive cervical carcinoma. There were no significant differences in the distribution of p53 genotypes between controls and cervical carcinomas. This finding indicates that the p53Arg genotype is not associated with an increased susceptibility to cervical carcinoma in Korean women.

Alleles↗
PubMed2000

Collagen-to-smooth muscle ratio helps prediction of prognosis after pyeloplasty.

PURPOSE: We quantitatively evaluated the collagen-to-smooth muscle tissue matrix ratio in ureteropelvic junction obstruction, and compared the ratio with the degree of obstruction, patient age and postoperative renal recovery. MATERIALS AND METHODS: We analyzed histological sections from 65 patients with ureteropelvic junction obstruction and 6 normal controls. Morphological and functional grading systems were adapted to determine the degree of renal obstruction. To examine smooth muscle and collagen tissue, sections were stained using Masson's trichrome. Two distinct populations of collagen versus smooth muscle were identified and the tissue matrix ratio was calculated by color image analysis. RESULTS: The mean tissue matrix ratio plus or minus standard deviation was 1.32+/-0.79 in all patients with ureteropelvic junction obstruction but only 0.30+/-0.10 in normal controls (p <0.0001). It appeared that the lower the tissue matrix ratio, the better the improvement in postoperative hydronephrosis (r = -0.50, p = 0.0001). Better recovery of renal function after pyeloplasty was observed with a decrease in the tissue matrix ratio (r = -0.43, p = 0.0004). We divided patients according to the tissue matrix ratio into groups 1--ratio 1 or less, 2--greater than 1 to 1.5 and 3--greater than 1.5 to determine a more detailed and clinically applicable correlation of tissue matrix ratio with postoperative renal functional changes. Better improvement in postoperative renal function was observed in group 1 than in group 3 (p = 0.002). Also, the tissue matrix ratio increased with patient age (r = 0.33, p = 0.007). CONCLUSIONS: Since our data represent an objective and quantitative parameter associated with ureteropelvic junction obstruction, we believe that our findings may help to predict the prognosis after pyeloplasty.

Child↗
PubMed1999

Stereoisomeric acylamidomorpholinium carnitine analogues: selective inhibitors of carnitine palmitoyltransferase I and II.

Acylamidomorpholinium carnitine analogues, 6-(tetradecanamidomethyl- and -hexadecanamidomethyl)-4,4-dimethylmorpholin-4-ium-2-a cetate, 1, synthesized as complete sets of stereoisomers, were assayed as inhibitors for isozymes of carnitine palmitoyltransferase (CPT). Microsomal CPT isoymes showed modest discrimination among the stereoisomers; while rat-liver mitochondrial CPT-I and CPT-II showed distinct differences. The tetradecanamidomethyl analogue of (2R,6S)-1 activated CPT-I but inhibited CPT-II.

Animals↗
PubMed1999

Erythrophagocytosis and iron deposition in atherosclerotic lesions.

Iron deposition has been shown to be prominent in atherosclerotic lesions. However, the source of iron accumulated in arterial walls is unclear. In present report, we provide the histological evidence to demonstrate the localization of erythrocytes in atherosclerotic lesions from experimental animals. As revealed by scanning and transmission electron microscopy, the circulating erythrocytes were found to be present in intima of atherosclerotic aortas from apoE-deficient mice. These erythrocytes appeared to be readily phagocytosed by macrophages in lesions. The erythrophagocytosis was also evident in lesions from cholesterol-fed rabbits. Furthermore, the iron deposition was detectable in the region with erythrocytes. When the aortic sections of humans and apoE-deficient mice were immunostained with specific antibody to hemoglobin, it was clearly shown that the positive stain was detectable in macrophage-derived foam cells. Immunostaining of serial sections with specific antibodies to heme oxygenase-1 (HO-1) and ferritin further demonstrated the colocalization of HO-1 and ferritin in area with positive immunoreactivity for hemoglobin. Likewise, Perls' reaction revealed the positive iron stain in the same region. Collectively, these results suggest that hemoglobin/heme released from the phagocytosed erythrocytes may contribute to at least part of iron deposited in atherosclerotic lesions.

Animals↗
PubMed1999

Iron-deficient diet reduces atherosclerotic lesions in apoE-deficient mice.

BACKGROUND: Iron deposition is evident in human atherosclerotic lesions, suggesting that iron may play a role in the development of atherosclerosis. To test this idea, the correlation between the extent of iron deposition and the severity of atherosclerosis in apolipoprotein E (apoE)-deficient mice was investigated. Furthermore, the effect of a low-iron diet on the progression of atherosclerotic lesions in these animals was evaluated. METHODS AND RESULTS: Iron deposition in tissues of apoE-deficient mice was examined by Perls' staining method. The results clearly demonstrated that iron deposits are present in atherosclerotic lesions and tissue sections of heart and liver in an age-dependent manner. When the young mice received a low-iron diet for 3 months, the hematocrit, serum iron, hemoglobin, and cholesterol concentrations were not significantly altered compared with those of littermates placed on a chow diet. However, the serum ferritin level of animals in the iron-restricted group was 27% to 30% lower than that of the control group in either sex. Furthermore, the lipoproteins isolated from the iron-restricted group exhibited greater resistance to copper-induced oxidation. Histological examination revealed that atherosclerotic lesions developed in mice fed a low-iron diet were significantly smaller than those found in control littermates. Likewise, the iron deposition as well as tissue iron content was much less in aortic tissues of the iron-restricted animals. Circulating autoantibodies to oxidized LDL and immunostains for epitopes of malondialdehyde-modified LDL detected on lesions were also significantly lower in mice fed a low-iron diet. CONCLUSIONS: Iron deposition is closely associated with the progression of atherosclerosis in apoE-deficient mice. Restriction in dietary iron intake leads to significant inhibition of lesion formation in these animals. These results suggest that the beneficial effect of a low-iron diet may be mediated, at least in part, by the reduction of iron deposition as well as LDL oxidation in vascular lesions.

Alkaline Phosphatase↗
PubMed1999

A new study of bacterial motion: superconducting quantum interference device microscopy of magnetotactic bacteria.

The recently developed "microscope" based on a high-Tc dc SQUID (superconducting quantum interference device) is used to detect the magnetic fields produced by the motion of magnetotactic bacteria, which have permanent dipole moments. The bacteria, in growth medium at room temperature, can be brought to within 15 micron of a SQUID at liquid nitrogen temperature. Measurements are performed on both motile and nonmotile bacteria. In the nonmotile case, we obtain the power spectrum of the magnetic field noise produced by the rotational Brownian motion of the ensemble of bacteria. Furthermore, we measure the time-dependent field produced by the ensemble in response to an applied uniform magnetic field. In the motile case, we obtain the magnetic field power spectra produced by the swimming bacteria. Combined, these measurements determine the average rotational drag coefficient, magnetic moment, and the frequency and amplitude of the vibrational and rotational modes of the bacteria in a unified set of measurements. In addition, the microscope can easily resolve the motion of a single bacterium. This technique can be extended to any cell to which a magnetic tag can be attached.

Biophysical Phenomena↗